There's some disagreement as to which version of the MS-05 Zaku was produced when. In theory, there are two major versions. The MS-05A was the early version which was used to organize the original Mobile Training Battalion, and the MS-05B was the standard production model.

According to most Universal Century timelines, the MS-05 series begins with the rollout of a prototype version in February of U.C. 0074. A combat-ready version is completed in either May or August of U.C. 0075, followed by the formation of the Mobile Training Battalion in November. The following year, the Principality of Zeon expands its production facilities and begins full-scale mass production.

Since the combat-ready version introduced in U.C. 0075 enters production before the Mobile Training Battalion is formed, I believe this model would be the MS-05A Zaku. The production of this version ends in February of U.C. 0076, and mass production of the MS-05B presumably begins shortly afterwards, following the expansion of the Principality's production facilities in April of that year.

As for the February of U.C. 0074 event, Gundam Century originally used this date for the rollout of the prototype MS-03, the first mobile suit designed for combat use. MS Era claims that the MS-02, MS-03, and MS-04 are all completed during this year. These explanations seem plausible to me given the timing, and I've included them in this timeline.

As usual, sources differ as to which version of the Zaku II was introduced when. Although the Perfect Grade Zaku II kit manual says production begins with the MS-06A Zaku II, then shifts to the MS-06C in June of U.C. 0078 and finally to the MS-06F in December of that year, the Master Grade Zaku II kit manual claims that production shifts to the MS-06C at an early stage and that the MS-06F and MS-06J are introduced in September of U.C. 0078. Gundam Officials claims that production of the MS-06J begins in October of that year, and that production shifts to the MS-06F in December. Meanwhile, Entertainment Bible 1 maintains that the MS-06F isn't introduced until after the signing of the Antarctic Treaty on January 31, U.C. 0079.

Of these conflicting accounts, I think the Master Grade kit manual and Gundam Officials are the most plausible. Since the Principality of Zeon deploys hundreds of MS-06F and MS-06J units in its Earth invasion, there simply wouldn't be time to produce all these machines in the single month following the Antarctic Treaty. But if these new models are instead introduced in September of U.C. 0078, and produced in large numbers during the national mobilization that begins in October of that year, then the Principality has plenty of time to build all these machines.

As for Entertainment Bible 1's claim that the MS-06C has extra radiation shielding for nuclear warfare, which is then eliminated from the MS-06F after the Antarctic Treaty bans the use of nuclear weapons, we'll have to write it off as an obsolete anachronism. Most other sources describe the MS-06F as a minor upgrade with improvements to its power system, cockpit, and weapons payload. Although the MS-06C makes up the vast majority of the Principality's mobile suit forces during the first month of the war, that's presumably just because it's been in service longer than the new version.

There's some disagreement as to the number of people killed in the various cataclysmic events at the beginning of the One Year War. The Japanese publications generally agree that 3 billion people die as a result of the attacks on Sides 1, 2, and 4 during the One Week Battle, but there's no real agreement as to the effects of Operation British and the Battle of Loum.

Regarding Operation British, Gundam Century and Entertainment Bible 1 state that 320 million people are killed in the impact itself and an additional 2 billion in its aftermath. Entertainment Bible 1 adds that the total casualties of the One Week Battle, including Operation British and the attacks on Sides 1, 2, and 4, amount to 5.5 billion people. On the other hand, Entertainment Bible 39 says that the entire One Week Battle claims a total of 3 billion lives, including 2.8 billion from the attacks on the colonies and 200 million from the initial impact of Operation British, and provides no figures for the secondary casualties caused by the aftereffects of the colony drop.

As for the casualties of the Battle of Loum, the available published estimates range from 2.0 to 3.5 billion, but these figures seem too large for a single colony cluster. According to Gundam Historica 02, Side 5 isn't even completed at this point, and only 30 of its planned 42 colonies are in place. Based on the claims of Gundam Century and Entertainment Bible 1 regarding Operation British, it would appear that the vast majority of the war's casualties took place during the One Week Battle rather than the Battle of Loum.

In compiling this timeline, I was particularly concerned with the issue of transit times within the Earth Sphere. Most such travel involves journeys of about 384,000 kilometers, the distance between Earth and the moon. Lagrange points 3, 4, and 5, which lie along the moon's orbital path, are equally far from Earth, and Lagrange points 4 and 5 lie the same distance from the moon as well. Lagrange points 1 and 2, which are located roughly 60,000 kilometers in front of and behind the moon, are essentially within the same neighborhood.

In the Apollo moon missions of the 20th century, this journey took roughly three days (72 hours), and the return trip about two and a half days (60 hours). The results should be similar for any spacecraft which is trying to use its fuel efficiently, regardless of the technology used, since an object traveling faster than this will overshoot its target and must expend more propellant to correct its course. Therefore, journeys of this order should normally take two or three days even for the spacecraft of the Universal Century.

However, space colonies and asteroid fortresses don't sit squarely on their respective Lagrange points, but instead circle them in what are known as halo orbits. Objects at Lagrange points 4 and 5, for example, move in an elliptical halo orbit that takes 89 days to complete and is approximately 400,000 kilometers wide at its widest point. As a result, an object orbiting Lagrange point 5 may find itself 600,000 kilometers from the moon at one point in its orbital cycle, and just 200,000 kilometers away at its closest approach. Travel times between these Lagrange points and the lunar neighborhood would thus be highly variable.

The events of Gundam 0083 provide us with an extreme scenario. After an attack on the Federation Forces fleet in the Sea of Solomon at Lagrange point 5, both sides dispatch forces to intercept a runaway colony en route to the moon. Anavel Gato's forces arrive at the moon roughly 20 hours later as part of the colony escort fleet, having received supplies en route, while the Federation fleet attempts to make the trip in about 15 hours and ends up trapped in lunar orbit with its propellant expended. Clearly, this kind of rapid travel is reserved for emergencies.

I've used these guidelines to evaluate the various departure and arrival times cited in the Japanese publications. According to Entertainment Bible 39's account of the Battle of Loum, Dozle Zabi's space fleet travels from Solomon to Side 5 in exactly 40 hours, which sounds perfectly reasonable. The same publication also claims that the Federation's 1st Combined Fleet travels from Luna II to Side 5 in just over 37 hours, which seems highly unlikely given the far greater distance traveled.

Gundam Historica 03 provides a detailed map charting the progress of the Principality of Zeon's Earth invasion. For purposes of this timeline, I've attempted to describe the locations shown on this map by referring to geographical landmarks and, in some cases, present-day national boundaries. The nations and borders of the modern world, however, have largely vanished by the time of the Universal Century.

Since the development histories of the MS-06R-2 Zaku II and the MS-09R Rick Dom are intertwined, I'll deal with these in a single footnote.

The development of the original MS-09 Dom is fairly straightforward. Gundam Officials claims that the basic design for this machine is completed in June, U.C. 0079, and according to Mobile Suit Variation 2 and the 1/144 Prototype Dom kit manual the first prototype unit rolls out more than six months after the start of the war, which would mean July. And finally, the Master Grade MS-09 Dom manual says that production of the standard version begins in late September.

Meanwhile, the Principality of Zeon's space forces adopt the MS-09R Rick Dom, a space version of the Dom, as a replacement for the MS-06F Zaku II. Most sources agree that the Rick Dom was selected over a rival candidate, the improved MS-06R-2 Zaku II, but there are conflicting accounts as to when this choice was actually made. The Mobile Suit Variation series indicates that these machines were intended as stopgap substitutes, filling the void created when the appearance of the RX-78 Gundam led the Principality to restart the development of its next-generation mobile suits from scratch. Gundam Century and the Zeon Military File say that the choice was made earlier as part of a regular update program, and the latter source claims that the MS-06R-2 Zaku II was evaluated against the Rick Dom on July 31, U.C. 0079.

In weighing these two explanations, we'll first consider the MS-06R-2 Zaku II. After this machine is rejected in favor of the Rick Dom, the existing units are assigned to some of the Principality's top pilots, most famously Johnny Ridden. According to the Master Grade MS-06R-2 Johnny Ridden's Zaku II manual, Ridden's machine receives its final overhaul in October, U.C. 0079, a few days before Ridden abandons it and is transferred to the Ace Corps. Gundam Officials, meanwhile, says that Ridden flies this Zaku for two months. Taken together, these claims indicate that Ridden begins using his MS-06R-2 Zaku II in August, which meshes perfectly with the notion that this machine was evaluated and rejected on July 31.

It's unlikely, however, that the Rick Dom would be ready for testing at this early date. The Prototype Dom is only completed in July, U.C. 0079, and at that point production of the standard MS-09 model is still two months away. As of October 6 the Principality is still testing the MS-06RD4 Zaku II, which is generally described as a mockup created with prototype Rick Dom parts in order to gather test data, and MS ERA 0099 reports that deployment of the Rick Dom begins in October.

How to reconcile these conflicting development timelines? My rationalization is that the July 31 evaluation pits the MS-06R-2 Zaku II not against the Rick Dom itself, but against the idea of adapting the Rick Dom for space combat. Once this proposal is formally adopted, the development of the Rick Dom begins in earnest. Entertainment Bible 1 reports that the Rick Dom was created in only two months, which would thus be the time period from August to October, U.C. 0079.

I've assumed that the times given for events in space, including within space colonies, are specified in Coordinated Universal Time (UTC). This is the standard reference time used in the modern world, an updated equivalent of the traditional Greenwich Mean Time (GMT). For simplicity's sake I'll refer to this simply as "standard time."

For the most part, the times of events on Earth are specified in local time, as per their respective time zones. I've made an exception for events which involve travel between Earth and space, which are specified in terms of standard time whenever it's possible to identify the relevant time zone.

When it comes to the events of the original Mobile Suit Gundam series, matters are complicated by the contradictions between the original television series and the three-part movie compilation, which changes the order of many key events. Although this timeline is based on the television series continuity rather than the movies, I've tried to allow enough room for the events of both versions. As a result, in some places it diverges considerably from other published timelines.

The most dramatic differences are in the timing of Ramba Ral's death and the events that surround it. The standard Universal Century timeline leaves a one-month gap between Garma Zabi's funeral and the beginning of Operation Odessa, which correspond to episodes 12 and 24 of the television series. The White Base's various battles with Ramba Ral and his team, and its journey across Asia toward Odessa, are thus assumed to fall somewhere in this gap.

Entertainment Bible 39 attempts to fill in the details of this gap based on the continuity of the Gundam II movie compilation. According to its timeline, the White Base enters Asia on October 10, U.C. 0079. On November 2, the White Base receives orders to cross the Caspian Sea within three days, and on November 5 it suffers a final desperate attack from Ramba Ral on the western shore of the Caspian Sea. The survivors of Ramba Ral's team then launch a revenge attack on November 7, shortly after the launch of Operation Odessa. Gundam Officials reproduces this timeline, expanding the description of the October 10 event to include the events of TV episode 16, and thus providing two different deadlines for the Caspian Sea crossing. The Zeon News inserts a couple more events into this timeline, placing the events of TV episode 17 on October 12, and the events of episodes 18 and 19 on November 3, which leaves Amuro Ray wandering in Central Asia for three weeks after he deserts the White Base.

Any attempt to reconcile the events of the TV series with Entertainment Bible 39's timeline break down, however, when it comes to the events that follow Ramba Ral's death. Based on the animation, at least three nights pass between the White Base's emergency landing in episode 22 and the beginning of Operation Odessa. As a result, I've moved Ramba Ral's death forward in my timeline.

The date I selected for this event is October 15, which Gundam Officials gives as the White Base's original deadline for crossing the Caspian Sea. Since Entertainment Bible 39's movie-derived timeline indicates that the White Base crosses the Caspian Sea on schedule, I've applied the same assumption to the television series continuity. The events of episodes 18 and 19, which The Zeon News places two days before Ramba Ral's death, are accordingly shifted to October 13. This means that they happen the day after Amuro deserts the White Base, which is exactly what the animation suggests.

Constructing a chronology for the Blue Destiny side story proves to be surprisingly difficult, since the sources are so scarce and contradictory. The strategy guide books released for the original video game contained a partial timeline which has been used as a reference by some Japanese fan sites, but since I don't have the original source I'm reluctant to include this information. The Blue Destiny novelization also contains some information as to when the events of the story take place, but this is imprecise and inconsistent, and the date it cites for the battle at the California Base is contradicted by some recent sources.

In most cases, I've opted for the vague dates provided by the timeline in The Gundam Chronicles Ver.2. This timeline claims that the first encounter between the 11th Autonomous Mechanized Composite Corps and the Blue Destiny takes place in the middle of November, U.C. 0079, a claim which is echoed by the Blue Destiny novelization. Some other sources put this event at November 29, but the most recent model kit manual says that November 29 is the date when You Kajima is chosen as the Blue Destiny's pilot. The Blue Destiny novelization says that Kajima's second encounter with the Blue Destiny takes place half a month after the first one, and he is chosen as its pilot one day later, so this meshes nicely with the mid-November date for their initial encounter.

After Kajima becomes the Blue Destiny's pilot, he is immediately assigned to destroy an enemy missile base to support the attack on the California Base. (See footnote 10: Recapture of the California Base.) According to the original video game, this mission takes place just before the main battle and Kajima is immediately sent to join the attack on the California Base. The MS Boys comic places the attack on the missile base on the night of December 4, and I've used that date here. Some time later, Kajima pursues the stolen Blue Destiny Unit 2 into space, and I've placed this part of the story in the middle of December as per the timeline in The Gundam Chronicles Ver.2.

According to the Blue Destiny novelization, the Federation Forces launch a mopping-up operation at the California Base on December 15, U.C. 0079, and various other sources have also used this date for the recapture of the California Base. Recently, however, the manuals from model kits such as the Master Grade MSM-07 Z'Gok and HG Universal Century RX-79BD-2 Blue Destiny Unit 2 have claimed that this event takes place in early December. The timeline in The Gundam Chronicles Ver.2 also claims that the Midnight Fenrir corps are fighting at the California Base's final defense lines as of December 4, and are covering the escape of their allies on December 5, likewise suggesting an earlier date for this battle.

According to the Mobile Suit Variation books, the Federation Forces capture the California Base at a relatively early point in their North American counteroffensive, and by the end of December they're producing their own mobile suits on its assembly lines. The Zeon forces then flee eastward to bases such as Newport and Cape Canaveral, the final targets of the Federation counteroffensive. Meanwhile, Gundam Officials says that the Federation Forces carry out mopping-up operations in North America from December 5 to December 15. Since Blue Destiny specifically describes the battle at the California Base as a "mopping-up operation," it should logically be part of this process, and ever since the MSV series it's been established that the Federation counteroffensive moves eastward from the California Base to Newport and Cape Canaveral. Surely, then, the recapture of the California Base should mark the beginning of the mopping-up operations rather than the end.

With this in mind, I've shifted the date of this event to December 5. This meshes perfectly with the timing of the Midnight Fenrir missions from Zeonic Front, and reduces the time lag between You Kajima's receipt of the Blue Destiny and his first mission as its pilot.

Both Gundam Officials and the Gundam 0080 DVD liner notes place the start of Operation Rubicon at 23:00 hours on December 14, U.C. 0079, with the Principality forces arriving at Side 6 the following morning. Although consistent with the animation, this leaves only seven hours for the Principality forces to travel from the moon to Side 6, which seems ludicrously brief. (See footnote 4: Transit Times.)

I've thus moved this event forward one day, giving the Principality forces roughly thirty hours to complete their journey. However, this also obliged me to move some of the preceding events forward by the same amount. The earliest such change is the arrival of the RX-78NT-1 Gundam at Side 6, which Gundam Officials and the DVD liner notes place on December 12 and I've moved forward to December 11. Although this leaves only two days for the Gundam to reach Side 6, Gundam Officials claims that the Cyclops team returns to Granada on December 11, so I figured it was reasonable that the Gundam could complete its own journey in that time.

I've opted for the latter here, since it allows more time for the Federation fleet to prepare and for Char Aznable to travel to the California Base and launch in pursuit. Moreover, if the White Base leaves Earth and enters Side 6 at the beginning of December, then the characters of Gundam 0080 would already know of the Gundam's existence thanks to the White Base's televised battle with the Conscon Squadron. But most of all, it seems silly to leave the White Base drifting in space for three weeks waiting for the Battle of Solomon to begin.

Data Collection 2, meanwhile, says that the Federation's Tianem Fleet launches from Jaburo on December 14. At first glance this would appear to contradict the notion that the White Base launches on December 13, since the animation indicates that both events take place on the same day, at 19:00 and 21:00 hours respectively. However, since Jaburo is four hours behind standard time, these equate to 23:00 on December 13 and 01:00 on December 14 as far as space operations are concerned. See footnote 7: Local Time.

I wasn't entirely certain where to place this event in the timeline, but I made an educated guess in order to include it.

Mobile Suit Variation 2 says this incident takes place just before the Battle of A Baoa Qu, and that it involves an attack on the Federation's Tianem Fleet. (Admiral Tianem himself died in the Battle of Solomon, but it appears the nickname stuck.) There are two points at which the Federation Forces travel toward A Baoa Qu in separate groups - after the launch of Operation Star One on December 29, and after the ravaged Federation fleet regroups on December 31.

Of these two options, I've chosen the former one. The MSV Collection File notes that this attack buys the Principality time to complete A Baoa Qu's defensive garrison, and since only three hours elapse between the December 31 fleet reorganization and the start of the Battle of A Baoa Qu, this seems too brief a period for the attack to make a difference. Moreover, since the Federation Forces are able to deploy their fleets so as surprise the enemy during the battle itself, it seems unlikely that the Principality would have precise knowledge of the Federation fleet's movements at this point.

Placing this incident on December 30 rather than December 29 is a similar judgement call. I chose the later date in deference to the original claim that the attack comes just before the Battle of A Baoa Qu, and assumed that it was roughly simultaneous with Kycilia Zabi's own assault on the Federation's 13th Autonomous Fleet.

While many animated Gundam works have been adapted into text novels, these novelizations usually depart from the animated continuity so dramatically that they're of little value as timeline sources. But I've made an exception for the Gundam 0083 novelization, in which each scene is predeced by a date and time that meshes perfectly with the published timelines. This novelization is also edited by anime director Takashi Imanishi, giving it an extra degree of credibility.

The datelines given in the novelization, however, appear to reflect the point at which each scene begins rather than when key events within the scene take place. Thus these should be considered mere approximations rather than exact times. I've placed these events on the timeline without precise times, noting the approximate time based on the dateline of the corresponding scene.

The Gundam 0083 novelization also provides a handful of precise event times, particularly in the timeline at the beginning of the second novel, and I've inserted these directly into my own timeline.

The standard Universal Century timeline makes no reference to any of the events between the Audhumla's departure from New Hong Kong on July 8 of U.C. 0087, and the launch of Operation Apollo on August 10 of that year. As a result, we have no dates for the events of Zeta Gundam episodes 20 through 22, including Kamille Bidan's return to space and the combat debut of the Zeta Gundam itself. However, information from some secondary sources allows us to pin these events down a little more precisely.

To begin with, we know that Kamille and his Gundam Mark II return to space before Karaba's attack on the New Guinea base, which takes place on July 21 according to Gundam Ace 007. The Master Grade RX-178 Gundam Mark II manual claims that the Gundam Mark II undergoes an overhaul at the lunar city of Von Braun in late July, an event which obviously takes place after it returns to space.

On the other hand, this overhaul probably takes place before the Gundam Mark II is damaged in Zeta Gundam episode 21. Gundam Ace 007 claims that Paptimus Scirocco formally joins the Titans on July 27, U.C. 0087, and according to the animation Scirocco and the Titan fleet depart Gryps at least two days before the events of episode 21, so this episode wouldn't begin until July 29 at the absolute earliest. This doesn't really leave enough time for the damaged Gundam Mark II to reach Von Braun and complete its overhaul by the end of July. And anyway, the Gundam Mark II is back in service as of Zeta Gundam episode 22, which appears to take place immediately after the events of the previous episode.

Given the above, I'd say that the events of Zeta Gundam episodes 21 and 22 take place in early August of U.C. 0087, just before the launch of Operation Apollo. This also happens to be when Anaheim Journal claims the Zeta Gundam was deployed in the battlefield.

The timeline published in Entertainment Bible 2 says that the Axis forces adopt the new name of Neo Zeon on February 29, U.C. 0088, and most later publications have echoed this claim. However, this is contradicted by the Gundam ZZ animation.

In the animation itself, Axis leader Haman Karn first uses the name Neo Zeon in an address to her fleet in episode 22. The recent Encyclopedia of Gundam claims that the Axis forces adopt the new name on July 13, U.C. 0088, the date corresponding to episode 22. When the AEUG characters first hear the new name in episode 24, they are told that it represents the union of Axis with the Principality remnants on Earth, but presumably this alliance has already been established by the advance forces Haman has sent to Earth.

The official timelines for Zeta Gundam and Gundam ZZ include a number of gaps and distortions, mainly because the editors of Entertainment Bible 2 assigned most of the event dates based on the broadcast dates of the corresponding episodes. For example, the first episode of Zeta Gundam aired on March 2 of 1985, and the final episode aired on February 22 of 1986, so the official timeline says that the events of the series took place between March 2 of U.C. 0087 and February 22 of U.C. 0088. The same is also true of many events in Gundam ZZ, although the dates are one day off because U.C. 0088 is a leap year and 1986 A.D. is not.

While this works fairly well where Zeta Gundam is concerned, it creates a number of contradictions with the Gundam ZZ animation, in which the events of one episode often flow seamlessly into the next with no visible pauses. The most glaring example may be the sequence of events that spans episodes 17 through 19, in which Judau Ashta witnesses the destruction of an abandoned colony by the Argama's new weapon, immediately deserts the AEUG and flies to the asteroid base Axis in his core fighter, is rejoined by his comrades, returns to Axis in the ZZ Gundam, and finally escapes as the Argama fires on Axis. The flow of events appears to be continuous throughout, with only a brief gap for Judau's solo flight to Axis in his core fighter, but the expanded timeline published in Data Collection 6 claims that these events happen over a period of more than five weeks. The battle between the ZZ Gundam and the Qubeley Mark II in episode 19, and the Argama's attack on Axis in that same episode, are separated by eleven days in the timeline even though they directly follow each other in the animation.

In this case, the official timelines are so incompatible with the animation that it's tempting to dismiss them entirely. However, I've reproduced these dates in my own timeline for lack of a good alternative.

The official timeline for Gundam ZZ currently includes two separate events in which the Axis fleet dispatches advance forces to Earth. The early timeline published in Entertainment Bible 2 mentions only a single advance force, which descends to Earth on June 6 of U.C. 0088. This advance force is said to consist of a few space cruisers, which travel to Earth to establish alliances with local Principality remnants and prepare a beachhead for the main fleet. Although this event doesn't appear to be related to anything in the animation, the June 6 date may indicate that the editors intended it to parallel episode 14 of Gundam ZZ. According to the expanded timeline published in Data Collection 6, however, it takes place between episodes 19 and 20 of the series.

In addition to this initial advance force, the timeline in Data Collection 6 also says that a second landing operation takes place on July 13 of U.C. 0088, simultaneously with episode 22 of Gundam ZZ. No further details of this operation are provided.